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Nsx cranks awhile before starting?

Joined
19 April 2011
Messages
150
Location
Anaheim
I have a 2001 comptech supercharged nsx , when I go to start the car it cranks about 6 or 7 times before it starts. When I go to take off in first it seems to hiccup and hesitate. Once it's warmed up the stutter goes away, I'm thinking the main relay. My mechanic keeps saying it's the alternator but when I put a voltmeter to it, it reads 14.1 on the tester. My mechanic says the car has 94,000 miles it's almost time for the alternator to go out. When I go to start the car I let the fuel pump and everything pressurize before I start it. Any help would be greatly appreciated thanks.
 
LOL at alternator change do to the mileage of a car. Only reason i could see this causing this possibly is crap bearings causing a lot of drag maybe... I imagine it would be making noise if so and you could always pull of the accessory belt and spin it but i imagine that is a 1 in 1000 chance but i am wrong often
 
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Only thing I can think of if it would be the alternator, is because maybe it was refurbished or not as good quality since its off of a 1992 prelude.
 
+1 on fuel pump relay, also take a look at the main relay as well and examine for any defect in the soldering, that is one thing that will leave you stranded if it is bad, I went ahead and replace mine for preventive. Good luck
 
I checked the main relay but didn't really see anything out of the ordinary no cracks in the soulder either. Might be worth a shot to replace it anyway.
 
J-RnsxT & anesthesia,

Just for clarification, when you say "main fuel pump relay", you are talking about the solitary relay that is located immediately behind the driver seat?
 
J-RnsxT & anesthesia,

Just for clarification, when you say "main fuel pump relay", you are talking about the solitary relay that is located immediately behind the driver seat?

Thats the one, right behind the PASSENGER seat:smile:. Its about 100 bucks, dealer item I believe. The crack is very hard to detech at first. With almost 100K, its time to replace it. I bought spare just in case too.
 
J-RnsxT & anesthesia,

Just for clarification, when you say "main fuel pump relay", you are talking about the solitary relay that is located immediately behind the driver seat?

Let's eliminate the confusion right now.

1) Main Relay - Located behind passenger seat.
2) Fuel pump relay - Located behind driver seat.

There are diagrams in the service manual available in the Wiki section.
 
I'm curious has anyone replaced the fuel pump relay to actually resolve the long crank time issue?

I guess the second part to the question is that if people are having the problem intermittently (ie. phantom), can the relay actually have varied or intermittent connectivity? What I mean by this is that if the relay fires (you hear it click), is the connection to the fuel pump poor, such that there is resistance in the line resulting in less than the full amount electricity passing to the pump, thus the pump is failing to operate at full capacity?
 
Before starting the car, set the key in the "ON" position first and let the fuel pump build up fuel pressure. Takes 2-3 seconds before it stops. Then crank.

Give it a try.
 
Before starting the car, set the key in the "ON" position first and let the fuel pump build up fuel pressure. Takes 2-3 seconds before it stops. Then crank.

Give it a try.

Mine takes 10 seconds to start when cold....thats a LOT of cranks. And I always let the pump initialize.
 
Before starting the car, set the key in the "ON" position first and let the fuel pump build up fuel pressure. Takes 2-3 seconds before it stops. Then crank.

Give it a try.

^If I do this I have no problem. But if I just try to crank right away like my S2000, It takes a while.

Is this normal? Did the nsx do this when it was new? ie the s2000 is just a newer car and doesn't need to build up the pressure or does something need to be replaced on the nsx?

My dad's 89 mercedes has a long crank as well if you don't let the pump build up pressure.
 
Mine does that too. When its cold it starts on the dime however, if I drive her for a while and make a pit stop after she's warmed up it wont crank over. So what I have to do is take the key out and turn to let the fuel pump start and then crank her over and at the same time give it a little gas. After a couple of cranks, it turns over and starts. Keep in mind this only happend once in a while not consistently. I wonder if it might be fuel pump? Or pump relay? Ive changed main relay and fuel filter already.
 
Do these part numbers sound right?

009 39400-SL0-A01 RELAY ASSY., MAIN 001 1995 NSX 88.45

011 39797-SE0-003 RELAY ASSY., POWER (4P) (056700-7330) (DENSO) 002 1995 NSX 38.02

For Main Relay and fuel pump relay?
 
Mine does that too. When its cold it starts on the dime however, if I drive her for a while and make a pit stop after she's warmed up it wont crank over. So what I have to do is take the key out and turn to let the fuel pump start and then crank her over and at the same time give it a little gas. After a couple of cranks, it turns over and starts. Keep in mind this only happend once in a while not consistently. I wonder if it might be fuel pump? Or pump relay? Ive changed main relay and fuel filter already.

This happened a lot in my 1992 Prelude, same kind of symptom. Only happened when it was hot, etc. WHat happens is the relay itself gets hot and doesn't want to turn on the fuel pump. In the Prelude, it was one big relay under the dash (above the clutch pedal actually). Sounds like it is behind the seat is the NSX...
 
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